Poinsettia named Grostar

ABSTRACT

A new Poinsettia cultivar distinguished by large, bright red bracts, large, thick stems and leaves and a short growth habit is herein described. The stems of this plant are noticeably strong with short internodes, yet possessing a strong self-branching habit. As a flowering potted plant, it performs equally well as a single-stemmed, unpinched plant or a branched, pinched plant.

BACKGROUND OF THE NEW PLANT

This new Poinsettia originated as a seedling and was produced by me inmy greenhouses in Le Bois d'Angeac, France. I selected this plantbecause of its large bright red bracts, thick green leaves and thick redbracts, short growth habit, thick, strong stems and self-branchingcharacteristics. This new Poinsettia flowers equally well as either apinched, multiple branched plant or as an unpinched single stem plant.The plant's characteristics are unique, resulting in a plant which isrecognizable as being different from any other poinsettia cultivar. Ipropagated this new plant by vegetative cuttings through successivegenerations, which time and again has shown its thick stems and leaves,short stature and bright red bracts which have remained unchanged fromgeneration to generation.

DESCRIPTION OF THE DRAWING

My new variety of Poinsettia is illustrated by the accompanying fullcolor photographic drawing, the color being as true to that hereinspecified as is reasonably possible to obtain by conventionalphotographic procedures.

DESCRIPTION OF THE NEW PLANT

The following is a detailed description of this new poinsettia asobserved under greenhouse culture in Le Bois d'Angeac, France. Colordesignations are according to The R.H.S. Colour Chart published in 1966by The Royal Horticultural Society at London, England.

THE PLANT

Origin: Cross breeding of our own variety No. 51×our own variety No.222.

Classification:

Botanic.--Euphorbia pulcherrima.

Form: Shrub.

Height: Typically 135 cm after one year.

Growth habit: As a single stem, upright, but short. Leaves and bractsare unusually thick and large. The stems are thick and strong withclosely spaced nodes. I observed flowering stems of 30-35 cm length withred bract presentations 30-40 cm in diameter.

Branching: Upright with many stems producing a compact, bushy plant fullin appearance.

Growth rate: Very fast. No growth regulator is needed. Rooting ofvegetative cuttings occurs in 15-20 days under intermittent mist and theplant will flower in about 8 weeks under continuous long nightconditions and night temperatures of 16°-18° C. The number of branchespresented after pinching is normally 6-8.

Foliage: This plant has unusually large, thick and erect leaves having abrilliant green upper side and a light green underside, with the planeof the leaf blade nearly perpendicular to the stem. There is no leaftorsion. The leaves have no hair. The length from the apex to the baseof an average leaf is 5.5 cm and the width thereof at the widest pointis 13 cm. The larger leaves typically have leaf blades 14-16 cm long and10-12 cm wide and leaf petioles 6-7 cm long. The length from the leafbase to the petiole base is typically 3.2 cm. The color of the petiolesurface is reddish.

Leaf shape: Typical mature leaves are lanceolate in overall shape, theapex of a mature leaf being acuminate in shape and the base thereofbeing ovate in shape. Torsion is absent in the mature leaf.

Bracts: Generally there are 12 uniformly colored bright red bracts,typically thicker and larger than most poinsettia cultivars. Bract coloris very stable. Flower parts and bracts are retained 4 to 6 weeks. It isnot unusual for the larger bract-leaf blades to be 16-18 cm long and10-13 cm wide with short leaf petioles, 3-4 cm long, which are reddishin color. The short bract petioles result in a bract presentation with aclose, tight center. The large lower bracts are somewhat cascading whilethe plane of the smaller bract blades is nearly perpendicular to thestem axis.

Shape: In overall shape, the bracts are usually ovate with entiremargins and have an acute apex and a rotundate base.

Color:

Upper side.--RHS 50A.

Under side.--RHS 46D.

The cyathia are very large and always have one nectar cup. The cyathiakeeps very long, more than four weeks. The coloration of the cyathia isyellow-orange, and the cyathia exude very strongly.

I claim:
 1. A new and distinctive Poinsettia cultivar, substantially asherein shown and described, particularly distinguished by large, brightred bracts, large thick stems and leaves and a short, self-branchinggrowth habit.